Honing machine

ABSTRACT

A honing machine has a honing tool mounted in a chuck secured to a hollow rotatable power driven spindle, and a beam with a fulcrum between its ends, said beam being located within the machine. One end of the beam is connected to a non-rotatable first stone feed rod housed in the spindle, and the end of said first stone feed rod remote from the beam is connected to a second stone feed rod which is slidable in and rotatable with the spindle and carries a device for expanding the honing tool. The other end of the beam is connected by a rod to a lever having a fixed fulcrum, said lever forming part of stone pressure control means. A resiliently loaded member contacts the lever so as to urge the beam in a direction to expand the tool, and the point of contact of the member on the lever is a variable distance from the fulcrum of said lever.

United States Patent 1 [111 3,747,279 Cox et al. July 24, 1973 [54] HONING MACHINE lnventors: Alan John Cox; Bryan Charles Annetts, both of Cheltenham, England Delapena Honing Equipment Limited, Cheltenham, England Filed: Sept. 13, i971 Appl. No.2 179,633

Assignee:

Foreign Application Priority Data Sept. 19, 1970 Great Britain 44,733/70 v References Cited UNITED STATES PATENTS 8/1951 Hunt. .Q 51/346 X Primary Examiner-0thell M. Simpson Attorney-James E. Nolan et a1.

[57] ABSTRACT A honing machine has ahoning tool mounted in a chuck secured to a hollow rotatable power driven spindle, and a beam with a fulcrum between its ends, said beam being located within the machine. One end of the beam is connected to a non-rotatable first stone feed rod housed in the spindle, and the end of said first stone feed rod remote from the beam is connected to a second stone feed rod which is slidable in and rotatable with the spindle and carries a device for expanding the honing tool. The other end of the beam is connected by a rod to a lever having a fixed fulcrum, said lever forming part of stone pressure control means. A resiliently loaded member contacts the lever so as to urge the beam in a direction to expand the tool, and the point of contact of the member on the lever is a variable distance from the fulcrum 'of said lever.

24 Claims, 2 Drawing Figures 1 HONING MACHINE BACKGROUND OF INVENTION The invention relates'to a honing machine, and more particularly to a bore honing machine having an improved tool expanding mechanism.

SUMMARY OF INVENTION According to the invention, a honing machine comprises a beam having a fulcrum between its ends, one end of the beam being connected to a feed rod, movement of which is adapted to expand a honing tool, and the other end of the beam being connected to stone pressure control means which urge the beam to pivot about the fulcrum to expand the tool.

BRIEF DESCRIPTION OF DRAWINGS A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings of which:

FIG. 1 is a sectional plan view of a honing machine; and

FIG. 2 is a sectional view of the line 2-2 in FIG. 1 of part of the honing machine.

DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the drawings, a honing machine has a case in which a hollow main spindle 11 is rotatably mounted in bearings 12 and 13. One end of the main spindle 11 extends through an aperture 14 in the case 10 and has secured to it a chuck 15in which a honing tool 16 is located, said chuck being adjustable so as to make the honing tool 16 run true. The end of the main spindle 11 extending beyond the bearing 13 has secured to it a pulley 17 which forms part of a variable speed drive system (not shown) drivably connecting the main spindle 11 via a clutch (not shown) to an electric motor (not shown). The honing tool 16 has a honing stone 18 secured in a stone holder 19 mounted for radial movement in a slot 20 on one side of said tool and a wear element 21 is positioned on the other side of said tool diametrically opposite the honing stone 18. The stone holder 19 contacts a wedge-shaped member 22 which is slidable axially within the tool 16 and has a hooked end portion 23. A beam 24, formed of two parallel'plates 25 joined by a central web 26, is connected at one end by a pin 27 located in a slot 28 in the plates 25 to a first stone feed rod 29 slidable within the main spindle 11, the end of said rod adjacent the beam 24 being supported in a guide 30 formed in the case 10. The end of the first stone feed rod 29 remote from the beam 24 is screw-threaded and passes through a ball bearing 31, and is secured to the inner race of said bearing by clamping said race between a nut 32 on the screw-threaded end of the rod 29 and a flange 33 formed on the rod 29 adjacent its screw-threaded end. The outer race of the ball bearing 31 is a press fit within a bore 34 in a member 35, said member being slidable axially within and rotatable with the main spindle 11. The bearing 3] is retained in the member 35 by an extcrnally screw-threaded collar 36 which is screwed into the end of the bore 34. The end of the bore 34 remote from the beam 24 has a reduced diameter portion and a sleeve 37 fits within said bore so that an annular groove 38 is formed between said reduced diameter portion of the bore 34 and the end of the sleeve 37. A flange 39 formed at one end of a second stone feed rod 40 fits with minimal axial clearance and large radial clearance in the groove 38, enabling said flange to slide radially but not axially in said groove. The end of the second stone feed rod 40 remote from the beam 24 is a close sliding fit in the chuck 15 and has a recess 41 which engages the hooked end portion 23 of the wedge-shaped member 22. The beam 24 is pivotally connected by trunnions 42 to an internally screwthreaded sleeve 43 which is located between the plates 25 on an externally screw-threaded portion 44 of a stone feed spindle 45. The end of the stone feed spindle 45 adjacent the beam 24 is journalled in a plain bearing 46 in the case 10 and the end of said spindle remote from the beam 24 passes through a bore 47 formed in the case 10 and is secured to a calibrated handwheel 48. A collar 49 is secured to the spindle 45 by a pin 50 and is located within a sleeve 51 which is slidable on said spindle in an enlarged diameter portion of the bore 47. A compression spring 52 surrounding the spindle 45 is confined between the end of the enlarged diameter portion of the bore 47 and the end of the collar 49 adjacent the handwheel 48. The end of the sleeve 51 remote from the handwheel 48 is contacted by a bifurcated end of a lever 53 which is pivotally mounted on the casing 10. The end of the lever 53 remote from the sleeve 51 is connected by a linkage (not shown) to a foot pedal (not shown) which also operates the clutch (not shown). The plates 25 at the end of the beam 24 I remote from the main spindle 11 are connected together by a pin 54, which is also connected at its midpoint to one end of a rod 55. Movement of the beam 24 and the rod 55 is limited by stops 56 secured to the case 10 on each side of the beam 24. The other end of the rod 55 is connected to a lever 57 at a fixed distance from said levers fulcrum which is formed by pivotally connecting the lever 57 between two lugs 58 on the casing 10 by means of a pin 59 passing through both lugs 58 and the lever 57. A member 60 has a bifurcated end portion formed by arms 61 each of which is connected to a helical tension spring 62. The arms 61 of said bifurcated end portion pass on each side of the lever 57 and are joined by a knife edge portion 63 which contacts the lever 57. The ends of the springs 62 remote from the member 60 are connected to an arm 64 pivotally connected to the casing 10 and movable by means of an over-centre cam 65 connected to a hand lever 66. A spindle 67 having secured to it an edge-cam 68 is rotatably and slidably mounted at one end in a bearing 69 in a lug 70 on the casing 10. The other end of said spindle is connected to a calibrated handwheel 71 and adjacent said other end of the spindle 67 is supported in and passes through a bore 72 in the casing 10. The side of the edge-cam 68 adjacent the casing 10 has a conical projection 73 formed on it which engages a conical recess 74 formed in the casing 10 under the action of a helical compression spring 75 located on the spindle 67 between the lug 70 and the edge-cam 68. The member 60 is provided with a cam follower surface 76 which is held in contact with the edge-cam 68 by means of a helical tension spring 77 connected between one arm of a bifurcated extension 78 of said member which surrounds the spindle 67 and an anchorage point 79 on the casing 10. A dial indicator 80 is connected by a linkage 81 to a collar 82 secured on the rod 55.

In operation, initial depression of the foot pedal (not via the variable speed drive system (not shown) to the pulley 17 which in turn causes the main spindle 11, the chuck 15 and the honing tool 16 to rotate. Further depression of the foot pedal (not shown) causes the linkage (not shown) to pivot the lever 53 about its mounting point on the casing 10 so that the bifurcated end of said lever contacts the sleeve 51 and urges said sleeve into the enlarged diameter portion of the bore 47 against the action of the spring 52. As the collar 49, which is secured to the spindle 45 by the pin 50, is in contact with the sleeve 51 the spindle 45 also slides axially in the bore 47 and the bearing 46 causing the centre of the beam 24 which is connected to the sleeve 43 on said spindle to move towards the honing tool 16. This movement of the beam 24 is transmitted by the pin 27 to the stone feed rod 29 causing said rod to slide axially towards the honing tool 16 within the rotating main spindle 11. The axial movement of the non-rotating stone feed rod 29 is transmitted via the ball bearing 31 to the member 35, which rotates in unison with the main spindle 11, and thence via the groove 38 and the flange 39 to the rotatable stone feed rod 40. The movement of the stone feed rod 40 towards the honing tool 16 causes the wedge-shaped member 22 to slide axially into the honing tool 16 and expand the honing stone l8 radially outwards until said stone contacts the surface of the bore in the workpiece which is to be honed. When the honing stone 18 is in contact with said surface further movement of the spindle 45 towards the honing tool 16, limited by the end face of the sleeve 51 contacting the end face of the enlarged diameter portion of the bore 47, causes the beam 24 to pivot about the pin 27 located in the slot 28 and the consequent movement of the other end of the beam 24 is transmitted via the rod 55 to the lever 57. The lever 57 pivots about the pin 59 connecting said lever to the two lugs 58 on the casing 10 against the action of the springs 62. The point of action of the springs 62 on the lever 57 can be varied by moving the handwheel 71 towards the casing 10 against the action of the spring 75 to unlock the conical projection 73 from the conical recess 74 and then rotating said handwheel. Rotation of the handwheel 71 causes the edge-cam 68 to rotate with respect to the cam follower surface 76 and move the member 60 against the action of the spring 77, which maintains contact between said cam and said surface, to vary the point of contact between the knife edge por tion 63 and the lever 57 and thus to vary the pressure with which the honing stone 18 is urged against the surface of the bore in the workpiece. When the handwheel 71 is released the spring 75 urges the conical projection 73 into contact with the conical recess 74 formed in the casing 10 to lock the handwheel 71 in the selected position. A single 360 rotation of the handwheel 71 providcs complete variation of honing stone pressure within one range, and movement of the hand lever 66 and its associated cam 65 varies the position of the arm 64 forming the anchorage point for the springs 62 and provides an alternative range of honing stone pressures. The shape of the edge-cam 68 is chosen to provide highly sensitive adjustment of honing stone pressure at the low pressure end of each range. During the honing operation, the increasing diameter of the bore in the workpiece and wear of the honing stone 18 allow the stone feed rods 29, 40 to move towards the honing tool 16 under the action of the springs 62, causing the lever 57 to act via the rod 55 to urge the beam 24 to pivot about the trunnions 42. Thus movement of the lever 57 is directly proportional to the increasing diameter of the bore in said workpiece and the wear of the honing stone l8 and this is measured on the dial indicator 80 which is connected by the linkage 81 to the collar 82 on the rod 55. The required extent of radial movement of the honing stone 18 in the slot 20 of the honing tool 16 can be adjusted by rotation of the handwheel 48 which varies the position of the screw-threaded sleeve 43 and thus of the centre portion of the beam 24, to which said sleeve is connected by means of the trunnions 42, on the screw-threaded portion 44 of the stone feed spindle 45. This movement of the centre portion of the beam 24 results in corresponding movement of the stone feed rods 29, 40 and the wedge-shaped member 22, causing radial movement of the honing stone 18 relative to the honing tool 16. When the foot pedal (not shown) is released the stone feed spindle 45 moves under the action of the spring 52 to the position shown in FIG. 1 of the drawings, and the clutch (not shown) disengages the drive from the electric motor (not shown) to the pulley 17 on the main spindle 11. Said movement of the stone feed spindle 45 results in corresponding movement of the beam 24 and stone feed rods 29, 40 away from the honing tool 16 allowing the honing stone 18 to retract into said tool under the action of conventional spring means (not shown) which forms no part of the invention. From time to time, it will become necessary because of attrition of the wear element 21 to reposition the honing tool 16 centrally in the chuck 15. The connection of the stone feed rod 29 to the member 35 by means of the flange 39, with its large radial clearance in the groove 38, accommodates this repositioning of the honing tool 16 whilst still retaining the parallel relationship between the feed rods 29 and 40 necessary for transmitting axial thrust from one rod to the other without creating side thrust which would introduce undesirable vibration of the beam assembly and the dial indicator 80.

What we claim is:

l. A bore honing machine comprising a rotatable main spindle, a honing tool secured on said spindle, said tool having at least one stone mounted for radially outward movement; expander means within said honing tool for moving said stone radially outwardly, feed rod means operably connected to said expander means slidably mounted for movement axially within said spindle, a beam having a fulcrum between its ends and connected at one end to said feed rod means, stone pressure control means connected to the other end of said beam and comprising means for applying a manually adjustable spring force to said beam, means for moving said feed rod means to adjust the extend of radial outward movement of said stone, and means for moving said fulcrum to cause said feed rod means to move said stone radially outwardly into contact with the surface of a bore to be honed and subsequently to permit said spring force to be transmitted to said stone to urge it against said surface.

2. A bore honing machine according to claim 1, wherein the means for moving the feed rod to adjust the extent of the radially outward movement of the stone comprise means for adjusting the position of the fulcrum.

3. A bore honing machine according to claim 2, including a rotatable stone feed spindle having a screw thread portion, a screw-threaded sleeve on said screwthreaded portion, and means forming said beam fulcrum on said sleeve.

4. A honing machine according to claim 3, wherein the stone feed spindle is journalled in bearings at its ends and is rotatableto adjust the position of the fulcrum.

5. A bore honing machine according to claim 3,

' wherein said stone feed spindle is slidably mounted and resilient means is provided for moving said stone feed spindle to move said fulcrum so as to permit contraction of said honing tool.

6. A bore honing machine according to claim 5, wherein the stone feed spindle is operatively connected to a footpedal which slides said feed spindle against the action of said resilient means so as to expand the tool.

7. A honing machine according to claim 3, wherein the stone feed spindle is connected at one end to a calibrated handwheel.

8. A honing machine according to claim 1, wherein a dial indicator is operatively connected to the stone pressure control means.

9. A bore honing machine according to claim 1, wherein the feed rod means comprises a non-rotatable first stone feed rod housed in the main spindle, one end of said first stone feed rod being connected to the beam and the other end thereof being operatively connected to a second stone feed rod slidable in and rotatable with the main spindle and connected to the expander means.

10. A honing machine according to claim 9, wherein the non-rotatable first stone feed rod is movable axially of the main spindle and its end remote from the beam is so connected to a member rotatable with the main spindle as to be capable of sliding said member axially within the main spindle, said member being connected to the second stone feed rod.

11. A honing machine according to claim 10, wherein the first stone feed rod is connected to the member by a bearing having an outer race fixed to said member and an inner race fixed to said first stone feed rod.

12. A honing machine according to claim 10, wherein the main spindle is provided with a chuck in which the tool is mounted with its longitudinal as opposed to its rotational axis coinciding with or offset from but parallel to that of the main spindle, and the second stone feed rod is so connected to the member that the axis of said rod coincides with the longitudinal axis of the tool.

13. A honing machine according to claim 12, wherein the second stone feed rod has fixed on its end adjacent the first stone feed rod a flange which fits with minimal axial clearance in an internal annular groove formed in said member and of larger diameter than said flange, whereby the flange is slidable radially in the groove.

14. A bore honing machine according to claim 12, wherein the expander means comprise a wedge which has a hooked end disengagably secured in a recess near the end of the second stone feed rod remote from said member.

15. A honing machine according to claim 10, wherein the end of the first stone feed rod remote from said member is connected to the beam by a pin-and-slot arrangement to permit axial movement of said rod uponangular movement of the beam about the fulcrum.

16. A bore honing machine according to claim 1, wherein the stone pressure control means comprise a lever having a fixed fulcrum; a connection at a fixed distance from said fixed fulcrum between the lever and the beam; and a member contacting the lever, urged by the spring force in a direction to cause the beam to expand the'tool, and adjustable towards and away from the fulcrum.

17. A bore honing machine according to claim 16, wherein the spring force is applied by at least one spring having alternative anchorage points.

18. A bore honing machine according to claim 17, wherein the alternative anchorage points are provided by an arm movable between two positions by an adjustably mounted over-centre cam.

19. A honing machine according to claim 16, wherein said member is adjustable towards and away from the fulcrum by means of a cam.

20. A honing machine according to claim 19, wherein the cam for adjusting the member towards and away from the fulcrum is connected to a calibrated handwheel.

21. A honing machine according to claim 20, wherein the handwheel is capable of limited axial movement and is secured to one element of a locking device which is urged resiliently into contact with another element thereof which is fixed.

22. A honing machine according to claim 21, wherein the locking device is a conical friction brake.

23. A honing machine according to claim 19, wherein the cam for adjusting the member towards and away from the fulcrum is an edge cam.

24. A honing machine according to claim 23, wherein the member is held in contact with the cam by resilient means. 

1. A bore honing machine comprising a rotatable main spindle, a honing tool secured on said spindle, said tool having at least one stone mounted for radially outward movement, expander means within said honing tool for moving said stone radially outwardly, feed rod means operably connected to said expander means slidably mounted for movement axially within said spindle, a beam having a fulcrum between its ends and connected at one end to said feed rod means, stone pressure control means connected to the other end of said beam and comprising means for applying a manually adjustable spring force to said beam, means for moving said feed rod means to adjust the extend of radial outward movement of said stone, and means for moving said fulcrum to cause said feed rod means to move said stone radially outwardly into contact with the surface of a bore to be honed and subsequently to permit said spring force to be transmitted to said stone to urge it against said surface.
 2. A bore honing machine according to claim 1, wherein the means for moving the feed rod to adjust the extent of the radially outward movement of the stone comprise means for adjusting the position of the fulcrum.
 3. A bore honing machine according to claim 2, including a rotatable stone feed spindle having a screw thread portion, a screw-threaded sleeve on said screw-threaded portion, and means forming said beam fulcrum on said sleeve.
 4. A honing machine according to claim 3, wherein the stone feed spindle is journalled in bearings at its ends and is rotatable to adjust the position of the fulcrum.
 5. A bore honing machine according to claim 3, wherein said stone feed spindle is slidably mounted and resilient means is provided for moving said stone feed spindle to move said fulcrum so as to permit contraction of said honing tool.
 6. A bore honing machine according to claim 5, wherein the stone feed spindle is operatively connected to a foot pedal which slides said feed spindle against the action of said resilient means so as to expand the tool.
 7. A honing machine according to claim 3, wherein the stone feed spindle is connected at one end to a calibrated handwheel.
 8. A honing machine according to claim 1, wherein a dial indicator is operatively connected to the stone pressurE control means.
 9. A bore honing machine according to claim 1, wherein the feed rod means comprises a non-rotatable first stone feed rod housed in the main spindle, one end of said first stone feed rod being connected to the beam and the other end thereof being operatively connected to a second stone feed rod slidable in and rotatable with the main spindle and connected to the expander means.
 10. A honing machine according to claim 9, wherein the non-rotatable first stone feed rod is movable axially of the main spindle and its end remote from the beam is so connected to a member rotatable with the main spindle as to be capable of sliding said member axially within the main spindle, said member being connected to the second stone feed rod.
 11. A honing machine according to claim 10, wherein the first stone feed rod is connected to the member by a bearing having an outer race fixed to said member and an inner race fixed to said first stone feed rod.
 12. A honing machine according to claim 10, wherein the main spindle is provided with a chuck in which the tool is mounted with its longitudinal as opposed to its rotational axis coinciding with or offset from but parallel to that of the main spindle, and the second stone feed rod is so connected to the member that the axis of said rod coincides with the longitudinal axis of the tool.
 13. A honing machine according to claim 12, wherein the second stone feed rod has fixed on its end adjacent the first stone feed rod a flange which fits with minimal axial clearance in an internal annular groove formed in said member and of larger diameter than said flange, whereby the flange is slidable radially in the groove.
 14. A bore honing machine according to claim 12, wherein the expander means comprise a wedge which has a hooked end disengagably secured in a recess near the end of the second stone feed rod remote from said member.
 15. A honing machine according to claim 10, wherein the end of the first stone feed rod remote from said member is connected to the beam by a pin-and-slot arrangement to permit axial movement of said rod upon angular movement of the beam about the fulcrum.
 16. A bore honing machine according to claim 1, wherein the stone pressure control means comprise a lever having a fixed fulcrum; a connection at a fixed distance from said fixed fulcrum between the lever and the beam; and a member contacting the lever, urged by the spring force in a direction to cause the beam to expand the tool, and adjustable towards and away from the fulcrum.
 17. A bore honing machine according to claim 16, wherein the spring force is applied by at least one spring having alternative anchorage points.
 18. A bore honing machine according to claim 17, wherein the alternative anchorage points are provided by an arm movable between two positions by an adjustably mounted over-centre cam.
 19. A honing machine according to claim 16, wherein said member is adjustable towards and away from the fulcrum by means of a cam.
 20. A honing machine according to claim 19, wherein the cam for adjusting the member towards and away from the fulcrum is connected to a calibrated handwheel.
 21. A honing machine according to claim 20, wherein the handwheel is capable of limited axial movement and is secured to one element of a locking device which is urged resiliently into contact with another element thereof which is fixed.
 22. A honing machine according to claim 21, wherein the locking device is a conical friction brake.
 23. A honing machine according to claim 19, wherein the cam for adjusting the member towards and away from the fulcrum is an edge-cam.
 24. A honing machine according to claim 23, wherein the member is held in contact with the cam by resilient means. 